Hearing Aids

How do hearing aids work?

While there are many different styles and manufacturers of hearing aids, they are all built with the same basic parts: the microphone, the processor, the receiver (or speaker), and the battery.

The Microphone

Each hearing aid has one or more microphones. The microphone captures sound from the environment and converts it to an electrical signal that it sends to the processor.

The Processor

The processor modifies the signal from the microphone. Based on the capabilities and customized settings of each hearing aid, the signal can be modified in many ways, such as amplifying different sounds by different amounts, reducing background noise, managing feedback, and more! Discuss with your hearing care provider all the processing features and capabilities of the hearing aids recommended for you.

The Receiver (or Speaker)

This component converts the electrical signal in the processor back into sound and delivers it into the ear canal.

The Battery

Just like any other device, a hearing aid uses electrical power to function. You may choose a disposable battery option that could offer anywhere between 3 to 20 days of use before replacement; or a rechargeable battery; or a rechargeable hearing aid. Rechargeable batteries and hearing aids typically can sustain power all day after an overnight charge.

The Different Styles of Hearing Aids

There are six basic styles of hearing aids that you can choose from. When you consult a hearing healthcare provider, they will help you determine the style of hearing aid that is most suitable for you based on your hearing loss, listening challenges, and lifestyle needs.

BTE with slim tube and custom earmold, courtesy of Phonak — Image courtesy of Phonak

Behind-the-Ear (BTE) Hearing Aids

Behind-the-Ear hearing aids house the battery or power compartment, microphone, receiver, and processor behind the ear. Because BTE models house these components in the casing behind the ear, they are typically larger than other models, and some BTE models can provide the greater amplification needed for more severe hearing losses than smaller hearing aid styles. The casing behind the ear can be purchased in various colors to match the user’s skin tone or hair color. Once sound is detected and processed, it travels via a tube to the earpiece in the ear canal. Hearing healthcare providers can custom fit earpieces (also called earmolds) for maximum comfort and security or might recommend generic domes. This style is available for individuals with mild to profound hearing loss.

RIC hearing aid Courtesy of Oticon — Image courtesy of Oticon

Receiver-in-the-Canal (RIC) Hearing Aids

Similar to the BTE hearing aids, receiver-in-the-canal hearing aids are also worn behind the ear. They can be much smaller and more discreet because the receiver is not housed within the case. The case holds the microphone(s), battery, processor, and other components while the receiver sits inside the ear canal connected to the case by a small, nearly invisible tube. Hearing healthcare providers can custom fit earmolds for maximum comfort and security or might recommend general domes to retain the receiver. RIC hearing aids come in a variety of colors and are available for nearly all levels of hearing loss. They frequently offer rechargeable batteries and connectivity options such as Bluetooth.

Full Shell ITE hearing aid courtesy of Phonak — Image courtesy of Phonak

In-the-Ear (ITE) Hearing Aids

In-the-Ear hearing aids sit inside the folds of the outer ear and the ear canal in a lightweight custom shell made. They can range in size from half-shell to full-shell. Each size fills a different amount of the ear and has different amplification and feature options. ITE hearing aids are always custom made using an ear impression to mirror the wearer’s exact ear contours for comfort and security. If a hearing aid in each ear is needed, each ear will get its own ear impression and specialized hearing aid. Similar to a pair of shoes, ITE hearing aids may appear the same, but one will fit only the right ear and the other only the left, but not both. This style is suited for individuals with mild to severe hearing loss.

ITC hearing aid courtesy of Phonak — Image courtesy of Phonak

In-the-Canal (ITC) Hearing Aids

Just like the ITE models, in-the-canal options sit in the ear but more discreetly as they fit inside the ear canal with a smaller portion visible in the outer ear. ITC hearing aids are made for mild to severe hearing loss. Some smaller hearing aids have limited additional features and connectivity options.

CIC hearing aid courtesy of Oticon — Image courtesy of Oticon

Completely-in-the-Canal (CIC) Hearing Aids

The Completely-in-the-Canal option is even more discreet than ITC hearing aids. They are hardly visible to someone looking at the wearer’s ear as they fit into the ear canal with a faceplate visible at the opening. CIC hearing aids are suited for mild to moderate hearing loss. Some smaller hearing aids have limited additional features and connectivity options.

IIC hearing aid courtesy of Oticon — Image courtesy of Oticon

Invisible-In-Canal (IIC) Hearing Aids

Compared to the CIC option, invisible-in-canal hearing aids fit completely in the ear canal and are not visible when worn. The size and shape of the ear canal, degree of hearing loss, and the wearer’s dexterity are all considered by the hearing healthcare provider before suggesting this style. IIC hearings are better suited for those with mild to moderate hearing loss. Some smaller hearing aids have limited additional features and connectivity options.

Over-the-Counter (OTC) and Prescription Hearing Aids

As of October 2022, over-the-counter (OTC) hearing aids are a recognized category of hearing aids available to the public in the United States. The OTC hearing aid category established by the U.S. Food and Drug Administration authorizes certain hearing aids to be sold to people 18 years of age and older who have perceived mild to moderate hearing impairment, and these devices must meet certain performance specifications and device design requirements. Licensed and unlicensed professionals and retailers may sell, service, market, dispense, or distribute OTC hearing aids, and states have limited oversight over their sale.

Additionally, what has historically been known as a traditional hearing aid is now classified as a “prescription hearing aid.” Prescription hearing aids are defined as those that do not meet the requirements for the OTC category (for example, because they are intended for severe hearing impairment or users younger than age 18), and help those with mild, moderate, severe, and profound hearing loss. When choosing between an OTC and prescription hearing aid, IHS recommends consumers seek out the guidance of a hearing healthcare professional to ensure they receive the right device that best suits their needs.

Why Visit a Hearing Healthcare Professional

Although members of the public now have access to OTC hearing aids, they should still seek out the opinions and recommendations of a licensed and trained hearing healthcare professional. Not only do consumers have access to high-quality prescription hearing aids from these licensed practitioners, but they also receive continued care through the life of their hearing aids. These services can include routine maintenance, custom fitting, cleaning, alterations, customer support, and the knowledge that these specialists bring to their field. Hearing aid specialists dispense about half of the hearing aids delivered in the public market and operate in both urban and rural areas.

Members of the hearing healthcare profession continue their education and training by undergoing competency accreditation, testing, adhering to licensing and certification requirements, and participating in optional advanced certification programs. It is recommended that even those who plan to purchase OTC hearing aid devices first seek out the opinion of a hearing healthcare professional to help them navigate the pros and cons of these intricate and complex devices.

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